Search results for: Mohammad Aziz Shah Mohamed Arip
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3376

Search results for: Mohammad Aziz Shah Mohamed Arip

736 The Influence of Service Quality on Customer Satisfaction and Customer Loyalty at a Telecommunication Company in Malaysia

Authors: Noor Azlina Mohamed Yunus, Baharom Abd Rahman, Abdul Kadir Othman, Narehan Hassan, Rohana Mat Som, Ibhrahim Zakaria

Abstract:

Customer satisfaction and customer loyalty are the most important outcomes of marketing in which both elements serve various stages of consumer buying behavior. Excellent service quality has become a major corporate goal as more companies gradually struggle for quality for their products and services. Therefore, the main purpose of this study is to investigate the influence of service quality on customer satisfaction and customer loyalty at one telecommunication company in Malaysia which is Telekom Malaysia. The scope of this research is to evaluate satisfaction on the products or services at TMpoint Bukit Raja, Malaysia. The data are gathered through the distribution of questionnaires to a total of 306 respondents who visited and used the products or services. By using correlation and multiple regression analyses, the result revealed that there was a positive and significant relationship between service quality and customer satisfaction. The most influential factor on customer satisfaction was empathy followed by reliability, assurance and tangibles. However, there was no significant influence between responsiveness and customer satisfaction. The result also showed there was a positive and significant relationship between service quality and customer loyalty. The most influential factor on customer loyalty was assurance followed by reliability and tangibles. TMpoint Bukit Raja is recommended to device excellent strategies to satisfy customers’ needs and to adopt action-oriented approach by focusing on what the customers wanted. It is also recommended that similar study can be carried out in other industries using different methodologies such as longitudinal method, enlarge the sample size and use a qualitative approach.

Keywords: customer satisfaction, customer loyalty, service quality, telecommunication company

Procedia PDF Downloads 422
735 Development and Validation of Selective Methods for Estimation of Valaciclovir in Pharmaceutical Dosage Form

Authors: Eman M. Morgan, Hayam M. Lotfy, Yasmin M. Fayez, Mohamed Abdelkawy, Engy Shokry

Abstract:

Two simple, selective, economic, safe, accurate, precise and environmentally friendly methods were developed and validated for the quantitative determination of valaciclovir (VAL) in the presence of its related substances R1 (acyclovir), R2 (guanine) in bulk powder and in the commercial pharmaceutical product containing the drug. Method A is a colorimetric method where VAL selectively reacts with ferric hydroxamate and the developed color was measured at 490 nm over a concentration range of 0.4-2 mg/mL with percentage recovery 100.05 ± 0.58 and correlation coefficient 0.9999. Method B is a reversed phase ultra performance liquid chromatographic technique (UPLC) which is considered superior in technology to the high-performance liquid chromatography with respect to speed, resolution, solvent consumption, time, and cost of analysis. Efficient separation was achieved on Agilent Zorbax CN column using ammonium acetate (0.1%) and acetonitrile as a mobile phase in a linear gradient program. Elution time for the separation was less than 5 min and ultraviolet detection was carried out at 256 nm over a concentration range of 2-50 μg/mL with mean percentage recovery 100.11±0.55 and correlation coefficient 0.9999. The proposed methods were fully validated as per International Conference on Harmonization specifications and effectively applied for the analysis of valaciclovir in pure form and tablets dosage form. Statistical comparison of the results obtained by the proposed and official or reported methods revealed no significant difference in the performance of these methods regarding the accuracy and precision respectively.

Keywords: hydroxamic acid, related substances, UPLC, valaciclovir

Procedia PDF Downloads 222
734 Development of Drying System for Dew Collection to Supplement Minimum Water Required for Grazing Plants in Arid Regions

Authors: Mohamed I. Alzarah

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Passive dew harvesting and rainwater collection requires a very small financial investment meanwhile they can exploit a free and clean source of water in rural or remote areas. Dew condensation on greenhouse dryer cladding and assorted other surfaces was frequently noticed. Accordingly, this study was performed in order to measure the quantity of condensation in the arid regions. Dew was measured by using three different kinds of collectors which were glass of flat plate solar collector, tempered glass of photovoltaic (PV) and double sloped (25°) acrylic plexiglas of greenhouse dryer. The total amount of dew collection for three different types of collectors was measured during December 2013 to March 2014 in Alahsa, Saudi Arabia. Meteorological data were collected for one year. The condensate dew drops were collected naturally (before scraping) and by scraping once and twice. Dew began to condense most likely between 12:00 am and 6:30 am and its intensity reached the peak at about 45 min before sunrise. The cumulative dew yield on double-sloped test roof was varying with wind speed and direction. Results indicated that, wiping twice gave more dew yield compared to wiping once or collection by gravity. Dew and rain pH were neutral (close to 7) and the total mineralization was considerable. The ions concentration agrees with the World Health Organization recommendations for potable water. Using existing drying system for dew and rain harvesting cold provide a potable water source for arid region.

Keywords: PV module, flat plate solar collector, greenhouse, drying system, dew collection, water vapor, rainwater harvesting

Procedia PDF Downloads 305
733 Role of Kerala’s Diaspora Philanthropy Engagement During Economic Crises

Authors: Shibinu S, Mohamed Haseeb N

Abstract:

In times of crisis, the diaspora's role and the help it offers are seen to be vital in determining how many countries, particularly low- and middle-income nations that significantly rely on remittances, recover. Twenty-one lakh twenty thousand Keralites have emigrated abroad, with 81.2 percent of these outflows occurring in the Gulf Cooperative Council (GCC). Most of them are semi-skilled or low-skilled laborers employed in GCC nations. Additionally, a sizeable portion of migrants are employed in industrialized nations like the UK and the US. These nations have seen the development of a highly robust Indian Diaspora. India's development is largely dependent on the generosity of its diaspora, and the nation has benefited greatly from the substantial contributions made by several emigrant generations. Its strength was noticeable during the COVID-19 and Kerala floods. Millions of people were displaced, millions of properties were damaged, and many people died as a result of the 2018 Kerala floods. The Malayalee diaspora played a crucial role in the reconstruction of Kerala by providing support for the rescue efforts underway on the ground through their extensive worldwide network. During COVID-19, an analogous outreach was also noted, in which the diaspora assisted stranded migrants across the globe. Together with the work the diaspora has done for the state's development and recovery, there has also been a recent outpouring of assistance during the COVID-19 pandemic. The study focuses on the subtleties of diaspora philanthropic scholarship and how Kerala was able to recover from the COVID-19 pandemic and floods thanks to it. Semi-structured in-depth interviews with migrants, migrant organizations, and beneficiaries from the diaspora through snowball sampling to better understand the role that diaspora philanthropy plays in times of crisis.

Keywords: crises, diaspora, remittances, COVID-19, flood, economic development of Kerala

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732 Surface Sterilization Retain Postharvest Quality and Shelf Life of Strawberry and Cherry Tomato during Modified Atmosphere Packaging

Authors: Ju Young Kim, Mohammad Zahirul Islam, Mahmuda Akter Mele, Su Jeong Han, Hyuk Sung Yoon, In-Lee Choi, Ho-Min Kang

Abstract:

Strawberry and tomato fruits were harvested at the red ripens maturity stage in the Republic of Korea. The fruits were dipped in fungi solution and afterwards were sterilized with sodium hypochlorite (NaOCl) and chlorine dioxide (ClO2) gas. Some fruits were dipped in 150μL/L NaOCl solution for 10 minutes, and others were treated with 5μL/L ClO2 gas for 12 hours and packed with 20,000 cc OTR (oxygen transmission rate) film, the rest were packed in 10,000 cc OTR film inserted with 5μL/L ClO2 gas. 5μL/L ClO2 gas insert treatment showed the lowest carbon dioxide and ethylene, and the highest oxygen concentration was on the final storage day (15th day) in both strawberry and tomato fruits. Tomato fruits showed the lowest fresh weight loss in 5μL/L ClO2 gas insert treatment. The visual quality as well as shelf life showed the highest in 5μL/L ClO2 gas insert treatment of both strawberry and tomato fruits. In addition, the fungal incidence of strawberry and tomato fruits were the most suppressed in 5μL/L ClO2 gas insert treatment. 5μL/L ClO2 gas insert treatment showed higher firmness and soluble solids in both strawberry and tomato fruits. So, 5μL/L ClO2 gas insert treatment may be useful to prevent the fungal incidence as well as retaining the postharvest quality, and increase the shelf life of strawberry and tomato fruits for long term storage. This study was supported by Export Promotion Technology Development Program (314027-03), IPET, Ministry of Agriculture, Food and Rural Affairs, Republic of Korea.

Keywords: chlorine dioxide, ethylene, fungi, sodium hypochlorite

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731 Bond Strength of Different Strengthening Systems: Concrete Elements under Freeze–Thaw Cycles and Salt Water Immersion Exposure

Authors: Firas Al-Mahmoud, Jean-Michel Mechling, Mohamed Shaban

Abstract:

The long-term durability of fibre reinforced polymer (FRP) composites is often stated as being the main reason for the use of these materials. Indeed, structures externally or Near Surface Mounted (NSM) reinforced with Carbon Fibre Reinforcement Polymer CFRP are often in contact with temperature cycles and salt water immersion and other environmental conditions that reduce the expected durability of the system. Bond degradation is a frequent cause of premature failure of structural elements and environmental conditions are known to relate to such failures. The purpose of this study is to investigate the effect of environmental exposure on the bond for different CFRP strengthening systems. Bending tests were conducted to evaluate the bond with and without environmental exposure. The specimens were strengthened with CFRP sheets, CFRP plates and NSM CFRP rods embedded in two filling materials: epoxy resin and mortar. Then, they were exposed to up to 300 freeze–thaw cycles. One freeze–thaw cycle consisted of four stages according to ASTM or immersed in 3.5% salted tap water. A total of thirty-six specimens were prepared for this purpose. Results showed a decrease in ultimate bond strength for specimens strengthened by CFRP sheets that were immersed in salt water for 120 days, while a reduction was shown for CFRP sheet and plate bonded specimens that were subjected to 300 freeze–thaw cycles. Exposing NSM CFRP rod strengthened specimens, embedded in resin or mortar, to freeze–thaw cycles or to immersion in salt water does not affect the bond strength.

Keywords: durability, strengthening, FRP, bond, freeze–thaw

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730 Rival Conceptions of Sovereignty in Modern South Asian Political Thought: An Analysis Through the Writings of Maulana Syed Abul Ala Maududi and Maulana Hifzurrahman Seoharvi

Authors: Mohammad Saif

Abstract:

In the post-Westphalianworld order, the concept of sovereignty has been a fundamental area of inquiry in Political Science, International Relations, and International Law. Modern Islamic political thought has also dedicated a fair share of debate on the subject. The debate fundamentally revolves around the ‘ontological differentiation’ between western and Islamic political thought. While the centrality of the individual in western political thought regards the individual as the center of universe, Islamic Political thought provides that space to God. The modern liberal democratic principles suggest sovereignty as one of the major attributes of modern nation state; Islamists regard sovereignty as an attribute of God. However, the position regarding God’ssovereignty in Islamic political thought is not coherent in conception. Some scholars regard such a position as ‘the political interpretation of Islam’. This paper is an attempt to first analyze the fundamental discord between two rival political ideologies (western and Islamic), and then forward a debate on the subject of sovereignty in South Asian Islamic Political thought, particularly between Syed Abul Ala Maududi (ideological father of modern islamist movements) andHifzurrahmanSeoharvi (lesser known in Academia but highly influential in shaping Deobandi position of principles related to political nature of Islamic theology). Maududi regardssovereignty as an attribute of God and the rulers as subservient to Gods will, Seoharvi suggests that God's sovereignty does not entail that the caliph or amir cannot be a ruler or hakim, nor can his command or hukum be an order. Certain references have also been made to contemporary scholars like Sayidd Qutub, Rashid al Ghanouchi, who in one way or the other have contributed to the debate on ‘sovereignty in Islamic thought’.

Keywords: nation state, sovereigty, sovereignty of God (Hakimmiyah), deoband

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729 Jurisdictional Problem of International Criminal Court over National of Non-Parties: A Legal Analysis in the Light of Rome Statute

Authors: Nour Mohammad

Abstract:

The concept of International Criminal Court is not a new idea.It goes back to the late 19th century and was first mooted in 1872 by Gustave Moynier of the International Commitee of the Red Cross(ICRC). This paper attempts to focus on jurisdictional problem of the international criminal court (ICC) over national of states of non parties to the Rome statute. Mor than 120 countries are state parties to the Rome Statute representing all regions, Afria, the Asia-pacofoc Eastern Europe, Latin America and the Caribben as well as Western Europe and North America.The Statute is the core document of internationa criminal law todaycontaining 128 Articles and divided in 13 parts.The Rome Statute provides that the court may sit elsewhere the judge consider it desirable.The International Criminal Court is not in a position to adjudicate all international crimes but its jurisdiction is limited to the four categories of crime viz. genocide, crimes against humanity, war crimes and crime of aggression as stipulated in Article 5 of the ICC Statute. It also mention here that the Court will be able to exercise its jurisdiction over the crime of aggression only when this crime is defined. Due to the highly political nature of this crime, it is unlikely that a consensus in this regard would be arrived at in the near future.The main point of this article is to discuss the mandate of international criminal court to prosecute and punish persons responsible for the henious crimes of concern to the international community.The author highlighted the principles which support the delegation of criminal jurisdiction by state to international tribunals and discuss the precedents of such delegation.It also argued that the exercise of ICC jurisdiction over acts done pursuant to the officially policy of non-party state would not be contrary to the principles requiring consent for the exercise of jurisdiction by international tribunals. The article explore the limit to jurisdiction of ICC over non-party nationals.

Keywords: jurisdiction, international, criminal, court, non-parties

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728 Determination of Optimum Parameters for Thermal Stress Distribution in Composite Plate Containing a Triangular Cutout by Optimization Method

Authors: Mohammad Hossein Bayati Chaleshtari, Hadi Khoramishad

Abstract:

Minimizing the stress concentration around triangular cutout in infinite perforated plates subjected to a uniform heat flux induces thermal stresses is an important consideration in engineering design. Furthermore, understanding the effective parameters on stress concentration and proper selection of these parameters enables the designer to achieve a reliable design. In the analysis of thermal stress, the effective parameters on stress distribution around cutout include fiber angle, flux angle, bluntness and rotation angle of the cutout for orthotropic materials. This paper was tried to examine effect of these parameters on thermal stress analysis of infinite perforated plates with central triangular cutout. In order to achieve the least amount of thermal stress around a triangular cutout using a novel swarm intelligence optimization technique called dragonfly optimizer that inspired by the life method and hunting behavior of dragonfly in nature. In this study, using the two-dimensional thermoelastic theory and based on the Likhnitskiiʼ complex variable technique, the stress analysis of orthotropic infinite plate with a circular cutout under a uniform heat flux was developed to the plate containing a quasi-triangular cutout in thermal steady state condition. To achieve this goal, a conformal mapping function was used to map an infinite plate containing a quasi- triangular cutout into the outside of a unit circle. The plate is under uniform heat flux at infinity and Neumann boundary conditions and thermal-insulated condition at the edge of the cutout were considered.

Keywords: infinite perforated plate, complex variable method, thermal stress, optimization method

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727 Human Rights and Fundamental Freedoms in Crisis as Viewed during Bangladesh Parliamentary Election-2018 and Afterwards: A Contestant's Perspective on Social Measures

Authors: Mohammad S. Islam

Abstract:

Elections in Bangladesh are always controversial, and sometimes it becomes a violent affair when state power is combined with politics. Despite the commitment of the ruling party- the polling government to ensure free, fair, and credible elections, the participants of opposition parties and the general voters became very disappointed, terribly frustrated, and severely shocked. It happened when numerous claims of serious irregularities of vote rigging and violence came out in broad daylight during the election. This paper addresses the issues of how the ruling party created frightening and a horror situation to make people silent over electoral fraud and violent incidents, including gang rape. It also seeks to demonstrate that election-2018 was simply the deceptive action of the ruling party to legitimate their power, but not to provide a minimum opportunity for voters to exercise their fundamental right to vote. The fundamental freedom and the rule of law seemed to be ignored completely in this election process and afterwards. With the help of state machinery, the government of the ruling party violated human rights, restricted fundamental freedoms, and humiliated social protection & dignity. The contestant’s views as witnessed and relevant literatures are cited first for conceptual understanding. Then, the paper will examine how a new dimension of circumstantial social measures related to sustained protection can reduce all kinds of violence against humanity towards establishing a peaceful democratic society. Finally, this paper interprets the key findings and considers wider implications.

Keywords: electoral fraud, human rights, sustained protection, social measures, vote rigging

Procedia PDF Downloads 163
726 Application of a Compact Wastewater Treatment Unit in a Rural Area

Authors: Mohamed El-Khateeb

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Encompassing inventory, warehousing, and transportation management, logistics is a crucial predictor of firm performance. This has been extensively proven by extant literature in business and operations management. Logistics is also a fundamental determinant of a country's ability to access international markets. Available studies in international and transport economics have shown that limited transport infrastructure and underperforming transport services can severely affect international competitiveness. However, the evidence lacks the overall impact of logistics performance-encompassing all inventory, warehousing, and transport components- on global trade. In order to fill this knowledge gap, the paper uses a gravitational trade model with 155 countries from all geographical regions between 2007 and 2018. Data on logistics performance is obtained from the World Bank's Logistics Performance Index (LPI). First, the relationship between logistics performance and a country’s total trade is estimated, followed by a breakdown by the economic sector. Then, the analysis is disaggregated according to the level of technological intensity of traded goods. Finally, after evaluating the intensive margin of trade, the relevance of logistics infrastructure and services for the extensive trade margin is assessed. Results suggest that: (i) improvements in both logistics infrastructure and services are associated with export growth; (ii) manufactured goods can significantly benefit from these improvements, especially when both exporting and importing countries increase their logistics performance; (iii) the quality of logistics infrastructure and services becomes more important as traded goods are technology-intensive; and (iv) improving the exporting country's logistics performance is essential in the intensive margin of trade while enhancing the importing country's logistics performance is more relevant in the extensive margin.

Keywords: low-cost, recycling, reuse, solid waste, wastewater treatment

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725 Investigating Teachers’ Approaches in Teaching English and Students’ Communicative Ability in a Tertiary College

Authors: Adel Ben Mohamed

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The widespread use of the English language around the world has pushed many countries to consider such a language as a top priority in their educational system. One of these countries is the Sultanate of Oman. In this frame, the Omani government has allocated huge budgets as well as resources in order to implement the English language in its education system. The importance of English is prevalent in Oman. This is clearly noticeable through remarkable signs. For instance, most of the official documents in Oman are in both Arabic (the mother tongue) or English. In addition to that, there is a mushroom of English language institutes all over the country. In 2020, there are over fourteen English language institutes and centers in Oman (esl base, 2020). Moreover, these days most of the Omani parents are sending their children for tuition to learn the English language. Hence, it is apparent that the Sultanate of Oman is giving a great value to the importance of English in attaining various goals. However, in the world of work, what is more, important today is fluency rather than accuracy. Therefore, many people go for communication English rather than technical English. For example, Oman Daily Observer newspaper published a job advertisement of a sale assistant on 23rd of November 2020, recommended that speaking very well English is a must to be hired for the position (Oman Observer, 2020). In line with this and because of the great importance of the English language in Oman, the ministry of higher education has placed much emphasis on this official foreign language. Therefore, in the Omani educational system, all post -secondary students must sit for one year in one of the higher education institutions as a General Foundation Programmes (GFP) prior to moving to their respective majors in diploma level. Accordingly, the implementation of any teaching approach is determined by different factors: some are directly linked to teachers while others are related to organizational variables.

Keywords: teaching approaches, communicative, ability, investigating

Procedia PDF Downloads 65
724 Some Imaginative Geomorphosites in Malaysia: Study on Their Formations and Geotourism Potentials

Authors: Dony Adriansyah Nazaruddin, Mohammad Muqtada Ali Khan

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This paper aims to present some imaginative geomorphological sites in Malaysia. This study comprises desk study and field study. Desk study was conducted by reviewing some literatures related to the topic and some geomorphosites in Malaysia. Field study was organized in 2013 and 2014 to investigate the recent situation of these sites and to take some measurements, photographs and rock samples. Some examples of imaginative geomorphosites all over Malaysia have been identified for this purpose. In Peninsular Malaysia, some geomorphosites in Langkawi Islands (the state of Kedah) have imaginative features such as a “turtle” atop the limestone hill of Setul Formation at the Kilim Geoforest Park, a “shoe” at the Kasut island of the Kilim Geoforest Park, a “lying pregnant lady” at the Dayang Bunting island of the Dayang Bunting Marble Geoforest Park, and a “ship” of the Singa Kecil island. Meanwhile, some other examples are from the state of Kelantan, such as a mogote hill with a “human face looking upward” at Gunung Reng, Jeli District and a “boat rock” at Mount Chamah, Gua Musang District. In East Malaysia, there is only one example can be identified, it is the “Abraham Lincoln’s face” at the Deer Cave, Gunung Mulu National Park, Sarawak. Karst landforms dominate the imaginative geomorphosites in Malaysia. The formations of these features are affected by some endogenic and exogenic processes, such as tectonic uplift, weathering (including solution), erosion, and so on. This study will recommend that these imaginative features should be conserved and developed for some purposes, such as research, education, and geotourism development in Malaysia.

Keywords: geomorphosite, geotourism, earth processes, karst landforms, Malaysia

Procedia PDF Downloads 605
723 Evaluation of Anti-Pruritus Effect of Melatonin on Hemodialysis Patients with Uremic Pruritus: A Randomized Clinical Trial

Authors: Paria Baharvand, Mohammad Reza Abbasi, Soha Namazi

Abstract:

Introduction: Uremic pruritus (UP) is one of the major complaints in hemodialysis patients. The aim of this randomized clinical trial study was the evaluation of the anti-pruritus effect of Melatonin on hemodialysis patients with UP. Methods: This multi-centered double, blinded randomized clinical trial study was conducted on hemodialysis patients with UP that referred to the dialysis department of Imam Khomeini Hospital, Labbafinezhad Hospital and Ghiasi Hospital in Tehran, Iran, in 2018. Forty participants were enrolled and block randomization was performed by using a randomized list and divided into 2 groups of twenty patients. Evaluation of the 12-Item Pruritus Severity Scale (12-PSS), Visual analog scale (VAS), and Calculation of the affected body surface area for pruritus extent (BSA %) was performed every week. The Melatonin group received a 10 mg soft gel capsule, and the placebo group received a soft gel capsule placebo after dinner. For statistical analysis used by SPSS version 21(IRCT20180714040462N1). Results: 38 hemodialysis patients enrolled in this study. The mean age in the placebo group and in the Melatonin group was 55.88 ± 11.70 and 54.52 ± 13.00 years (p> 0.05). Also, 46% of all participants were female. Aspartate transaminase, alanine transaminase and C-reactive protein have significant differences between the two groups (p< 0.05). VAS score reduction in the two groups had a statistically significant (CI 95% = -1.71, P= 0.015(.The results of BSA% showed Melatonin had a significant effect on the decrease of the pruritus extent compared to placebo (CI 95% = -22.82, P= 0.001(. Conclusion: According to the results of this study and the preliminary effects of Melatonin on uremic pruritus, we suggest performing advanced clinical trials studies.

Keywords: Melatonin, Uremic Pruritus, hemodialysis, anti-pruritus

Procedia PDF Downloads 48
722 Numerical and Experimental Investigation of Fracture Mechanism in Paintings on Wood

Authors: Mohammad Jamalabadi, Noemi Zabari, Lukasz Bratasz

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Panel paintings -complex multi-layer structures consisting of wood support and a paint layer composed of a preparatory layer of gesso, paints, and varnishes- are among the category of cultural objects most vulnerable to relative humidity fluctuations and frequently found in museum collections. The current environmental specifications in museums have been derived using the criterion of crack initiation in an undamaged, usually new gesso layer laid on wood. In reality, historical paintings exhibit complex crack patterns called craquelures. The present paper analyses the structural response of a paint layer with a virtual network of rectangular cracks under environmental loadings using a three-dimensional model of a panel painting. Two modes of loading are considered -one induced by one-dimensional moisture response of wood support, termed the tangential loading, and the other isotropic induced by drying shrinkage of the gesso layer. The superposition of the two modes is also analysed. The modelling showed that minimum distances between cracks parallel to the wood grain depended on the gesso stiffness under the tangential loading. In spite of a non-zero Poisson’s ratio, gesso cracks perpendicular to the wood grain could not be generated by the moisture response of wood support. The isotropic drying shrinkage of gesso produced cracks that were almost evenly spaced in both directions. The modelling results were cross-checked with crack patterns obtained on a mock-up of a panel painting exposed to a number of extreme environmental variations in an environmental chamber.

Keywords: fracture saturation, surface cracking, paintings on wood, wood panels

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721 Job Satisfaction among Brigadista in Nicaragua: A Lesson to Be Considered for Task-Shifting

Authors: Rashed Shah, Jeanne Koepsell, Dixmer Rivera, Eric Swedberg, David Marsh

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Success of primary health care goals of health promotion and disease prevention may well be determined by community based health workers’ overall job satisfaction. It is also important to understand the ways community health workers perceive their jobs and the importance they give to the various factors influencing their job satisfaction, which is critical before making a decision for task-shifting and for expanding their scope of work. Although brigadistas are unpaid volunteers, they are formally recognized and receive support and supervision from the Ministry of Health in Nicaragua. Brigadistas are responsible for classifying and diagnosing illnesses, administering treatment, counseling mothers and care givers within the community, encouraging referral in case of serious illness and making follow-up visits at home. Some brigadistas provide more technically advanced services, including treatment for pneumonia, diarrhea, malaria and tuberculosis and/or distribution of contraceptives. Expanding brigadistas’ duties could threaten their heretofore ‘job satisfaction’. This study primarily aims to report on job satisfaction of brigadistas in Nicaragua before expanding the scope of their work by adding more responsibilities. The study was guided by the following research questions: 1) What aspects of their job made the brigadistas satisfied or dissatisfied? 2) What is the job satisfaction level of brigadistas in Nicaragua? This cross-sectional study was conducted during March – July 2014, to assess brigadistas’ job satisfaction, prior to deciding on inclusion of care for sick newborns and young infants (<2 months of age) to brigadistas’ existing service package of community case management for children of 2-59 months of age. Following stratified random sampling strategy, 15 brigadistas were randomly selected from each of the following four strata: [(1) females under 25 years of age, (2) females over 30 years of age, (3) males under 25 years of age, and (4) males over 30 years of age. Out of 45 completed in-person interview with eligible and available brigadistas, 20 (44.4%) were with female and 25 (55.6%) were with male respondents; the mean age (±sd) was found as 32.0 (±3.2) years. About 53% (24/45) brigadista mentioned “Training” as the most helpful for performing their job. Another 31% (14/45) mentioned that “feeling of doing good, supporting community, women and children” was helpful to perform their job well. When asked about difficulty, about 35.5% (16/45) brigadistas mentioned about “Lack of time” due to their responsibilities in family, farm, other work places, study and such time constraint made their job performance difficult. Measured on a 0-5 scale, estimated average job satisfaction was 4.2. Current trends in task-shifting and integrated program delivery require community health workers (like the brigadistas) to deliver several essential services, including maternal, newborn and child health, and family planning, and thereby increasing their responsibilities. Given the reported level of job satisfaction among brigadistas (4.2 out of 5), and the mentioned difficulty in performing their current job (as ‘Lack of Time’) in this study results, the policy makers and program managers in MOH should be cautious enough before making a decision to expand current scope of work for brigadistas in Nicaragua.

Keywords: Brigadisata, job satisfaction, Nicaragua, task-shifting

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720 Trends in Use of Millings in Pavement Maintenance

Authors: Rafiqul Tarefder, Mohiuddin Ahmad, Mohammad Hossain

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While milling materials from old pavement surface can be an important component of cost effective maintenance operation, their use in maintenance projects are not uniform and well documented. This study documents the different maintenance practices followed by four transportation districts of New Mexico Department of Transportation (NMDOT) in an attempt to find whether millings are being used in maintenance projects by those districts. Based on existing literature, a questionnaire was developed related to six common maintenance practices. NMDOT district personal were interviewed face to face to discuss and get answers to that questionnaire. It revealed that NMDOT districts mainly use chip seal and patching. Other maintenance procedures such as sand seal, scrub seal, slurry seal, and thin overlay have limited use. Two out of four participating districts do not have any documents on chip sealing; rather they employ the experiences of the chip seal crew. All districts use polymer modified high float emulsion (HFE100P) for chip seal with an application rate ranging from 0.4 to 0.56 gallons per square yard. Chip application rate varies from 15 to 40 lb/ square yard. State wide, the thickness of chip seal varies from 3/8" to 1" and life varies from 3 to 10 years. NMDOT districts mainly use three type of patching: pothole, dig-out and blade patch. Pothole patches are used for small potholes and during emergency, dig-out patches are used for all type of potholes sometimes after pothole patching, and blade patch is used when a significant portion of the pavement is damaged. Pothole patches last as low as three days whereas, blade patch lasts as long as 3 years. It was observed that all participating districts use millings in maintenance projects.

Keywords: chip seal, sand seal, scrub seal, slurry seal, overlay, patching, millings

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719 Hydro-Climatological, Geological, Hydrogeological and Geochemical Study of the Coastal Aquifer System of Chiba Watershed (Cape Bon Peninsula)

Authors: Khawla Askri, Mohamed Haythem Msaddek, AbdelAziz Sebei

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Climate change combined with the increase in anthropogenic activities will affect coastal groundwater systems around the world and, more particularly, the Cap Bon region in the North East of Tunisia. This study aims to study the impact of climate change and human stress on the salinization and quantification of groundwater in the Wadi Chiba watershed. In this regard, a hydro-climatological study and a hydrogeological study were carried out based on the characterization of the aquifer system of the eastern coast at the level of the watershed of Wadi Chiba in order to seek to identify, first of all, the degradation of the state of the aquifer on the quantitative level by the study of the piezometric and its evolution over time. Secondly, we sought to identify the degradation of the state of the aquifer qualitatively by using the geochemical method, in particular the major elements, to assess the mineralization of the aquifer water and understand its hydrogeochemical functioning. The study of the Na + / Cl- and Ca2 + / Mg2 + chemical relationships confirmed the presence of a marine intrusion downstream of the Wadi Chiba watershed northeast of Cap-Bon accompanied by a piezometric depression. For this purpose, we proceeded to: 1) Mapping of both piezometric data and salinity. 2) The interpretation of the mapping results. 3)Identification of the origin of the localized deterioration in the quality of the aquifer water. Finally, the analysis of the results showed that the scarcity of water is already forcing human actions in the Chiba watershed due to the irrigation of agricultural lands and the overexploitation of the water table in the study area.

Keywords: climate change, human activities, water table, Wadi Chiba watershed, piezometric depression, marine intrusion

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718 Impact of Aging on Fatigue Performance of Novel Hybrid HMA

Authors: Faizan Asghar, Mohammad Jamal Khattak

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Aging, in general, refers to changes in rheological characteristics of asphalt mixture due to changes in chemical composition over the course of construction and service life of the pavement. The main goal of this study was to investigate the impact of oxidation on fatigue characteristics of a novel HMA composite fabricated with a combination of crumb rubber (CRM) and polyvinyl alcohol (PVA) fiber subject to aging of 7 and 14 days. A flexural beam fatigue test was performed to evaluate several characteristics of control, CRM modified, PVA reinforced, and novel rubber-fiber HMA composite. Experimental results revealed that aging had a significant impact on the fatigue performance of novel HMA composite. It was found that a suitable proportion of CRM and PVA radically affected the performance of novel rubber-fiber HMA in resistance to fracture and fatigue cracking when subjected to long-term aging. The developed novel HMA composite containing 2% CRM and 0.2% PVA presented around 29 times higher resistance to fatigue cracking for a period of 7 days of aging. To develop a cumulative plastic deformation level of 250 micros, such a mixture required over 50 times higher cycles than control HMA. Moreover, the crack propagation rate was reduced by over 90%, with over 12 times higher energy required to propagate a unit crack length in such a mixture compared to conventional HMA. Further, digital imaging correlation analyses revealed a more twisted and convoluted fracture path and higher strain distribution in rubber-fiber HMA composite. The fatigue performance after long-term aging of such novel HMA composite explicitly validates the ability to withstand load repetition that could lead to an extension in the service life of pavement infrastructure and reduce taxpayers’ dollars spent.

Keywords: crumb rubber, PVA fibers, dry process, aging, performance testing, fatigue life

Procedia PDF Downloads 43
717 Conventional and Hybrid Network Energy Systems Optimization for Canadian Community

Authors: Mohamed Ghorab

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Local generated and distributed system for thermal and electrical energy is sighted in the near future to reduce transmission losses instead of the centralized system. Distributed Energy Resources (DER) is designed at different sizes (small and medium) and it is incorporated in energy distribution between the hubs. The energy generated from each technology at each hub should meet the local energy demands. Economic and environmental enhancement can be achieved when there are interaction and energy exchange between the hubs. Network energy system and CO2 optimization between different six hubs presented Canadian community level are investigated in this study. Three different scenarios of technology systems are studied to meet both thermal and electrical demand loads for the six hubs. The conventional system is used as the first technology system and a reference case study. The conventional system includes boiler to provide the thermal energy, but the electrical energy is imported from the utility grid. The second technology system includes combined heat and power (CHP) system to meet the thermal demand loads and part of the electrical demand load. The third scenario has integration systems of CHP and Organic Rankine Cycle (ORC) where the thermal waste energy from the CHP system is used by ORC to generate electricity. General Algebraic Modeling System (GAMS) is used to model DER system optimization based on energy economics and CO2 emission analyses. The results are compared with the conventional energy system. The results show that scenarios 2 and 3 provide an annual total cost saving of 21.3% and 32.3 %, respectively compared to the conventional system (scenario 1). Additionally, Scenario 3 (CHP & ORC systems) provides 32.5% saving in CO2 emission compared to conventional system subsequent case 2 (CHP system) with a value of 9.3%.  

Keywords: distributed energy resources, network energy system, optimization, microgeneration system

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716 Branding Good Corporate Governance: A Pathway to Strengthen Investors’ Perception and Brand Equity

Authors: Azaz Zaman, Imtiaz Uddin Chowdhury, Mohammad Shariful Islam

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Corporate governance has become a crucial issue in both the business and academic world as a result of world-wide financial scandals and lack of trust in corporate practices. There is no doubt that in order to thrive and attain growth in the market, a company must earn the trust of its stakeholders by consistently delivering on its commitments. Directors of the companies thus comprehend the importance of upfront communication with relevant stakeholders to increase their confidence. The authors of this article argue that practicing good corporate governance is not enough in this highly competitive market place; corporate leaders need to market their good corporate governance practices in order to make the company more attractive to investors. This article also contends that the strength of corporate governance relies wholly upon the extent to which it is communicated simply, effectively and unceasingly to its stakeholders. The main objective of this study, therefore, is to explore the importance of branding good corporate governance in order to increase corporate brand equity, attract investors, and capture market share. A structured questionnaire comprising three sections and a total of 34 questions was prepared and surveyed by the authors among respondents residing in Bangladesh and who also have an academic and corporate background, to investigate the potential impact of branding good corporate governance in the market place. High mean values for individual questions and overall section depict that communicating and branding good corporate governance to the stakeholders will not only boost the investors’ confidence but also increase the corporate brand equity, yielding both profitable and sustainable business environment.

Keywords: brand equity, investors’ preference, good corporate governance, sustainable business environment

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715 Structural Health Monitoring of the 9-Story Torre Central Building Using Recorded Data and Wave Method

Authors: Tzong-Ying Hao, Mohammad T. Rahmani

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The Torre Central building is a 9-story shear wall structure located in Santiago, Chile, and has been instrumented since 2009. Events of different intensity (ambient vibrations, weak and strong earthquake motions) have been recorded, and thus the building can serve as a full-scale benchmark to evaluate the structural health monitoring method developed. The first part of this article presents an analysis of inter-story drifts, and of changes in the first system frequencies (estimated from the relative displacement response of the 8th-floor with respect to the basement from recorded data) as baseline indicators of the occurrence of damage. During 2010 Chile earthquake the system frequencies were detected decreasing approximately 24% in the EW and 27% in NS motions. Near the end of shaking, an increase of about 17% in the EW motion was detected. The structural health monitoring (SHM) method based on changes in wave traveling time (wave method) within a layered shear beam model of structure is presented in the second part of this article. If structural damage occurs the velocity of wave propagated through the structure changes. The wave method measures the velocities of shear wave propagation from the impulse responses generated by recorded data at various locations inside the building. Our analysis and results show that the detected changes in wave velocities are consistent with the observed damages. On this basis, the wave method is proven for actual implementation in structural health monitoring systems.

Keywords: Chile earthquake, damage detection, earthquake response, impulse response, layered shear beam, structural health monitoring, Torre Central building, wave method, wave travel time

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714 Non-Linear Load-Deflection Response of Shape Memory Alloys-Reinforced Composite Cylindrical Shells under Uniform Radial Load

Authors: Behrang Tavousi Tehrani, Mohammad-Zaman Kabir

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Shape memory alloys (SMA) are often implemented in smart structures as the active components. Their ability to recover large displacements has been used in many applications, including structural stability/response enhancement and active structural acoustic control. SMA wires or fibers can be embedded with composite cylinders to increase their critical buckling load, improve their load-deflection behavior, and reduce the radial deflections under various thermo-mechanical loadings. This paper presents a semi-analytical investigation on the non-linear load-deflection response of SMA-reinforced composite circular cylindrical shells. The cylinder shells are under uniform external pressure load. Based on first-order shear deformation shell theory (FSDT), the equilibrium equations of the structure are derived. One-dimensional simplified Brinson’s model is used for determining the SMA recovery force due to its simplicity and accuracy. Airy stress function and Galerkin technique are used to obtain non-linear load-deflection curves. The results are verified by comparing them with those in the literature. Several parametric studies are conducted in order to investigate the effect of SMA volume fraction, SMA pre-strain value, and SMA activation temperature on the response of the structure. It is shown that suitable usage of SMA wires results in a considerable enhancement in the load-deflection response of the shell due to the generation of the SMA tensile recovery force.

Keywords: airy stress function, cylindrical shell, Galerkin technique, load-deflection curve, recovery stress, shape memory alloy

Procedia PDF Downloads 164
713 Lateral Torsional Buckling Investigation on Welded Q460GJ Structural Steel Unrestrained Beams under a Point Load

Authors: Yue Zhang, Bo Yang, Gang Xiong, Mohamed Elchalakanic, Shidong Nie

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This study aims to investigate the lateral torsional buckling of I-shaped cross-section beams fabricated from Q460GJ structural steel plates. Both experimental and numerical simulation results are presented in this paper. A total of eight specimens were tested under a three-point bending, and the corresponding numerical models were established to conduct parametric studies. The effects of some key parameters such as the non-dimensional member slenderness and the height-to-width ratio, were investigated based on the verified numerical models. Also, the results obtained from the parametric studies were compared with the predictions calculated by different design codes including the Chinese design code (GB50017-2003, 2003), the new draft version of Chinese design code (GB50017-201X, 2012), Eurocode 3 (EC3, 2005) and the North America design code (ANSI/AISC360-10, 2010). These comparisons indicated that the sectional height-to-width ratio does not play an important role to influence the overall stability load-carrying capacity of Q460GJ structural steel beams with welded I-shaped cross-sections. It was also found that the design methods in GB50017-2003 and ANSI/AISC360-10 overestimate the overall stability and load-carrying capacity of Q460GJ welded I-shaped cross-section beams.

Keywords: experimental study, finite element analysis, global stability, lateral torsional buckling, Q460GJ structural steel

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712 Heterogeneous Photocatalytic Degradation of Ibuprofen in Ultrapure Water, Municipal and Pharmaceutical Industry Wastewaters Using a TiO2/UV-LED System

Authors: Nabil Jallouli, Luisa M. Pastrana-Martínez, Ana R. Ribeiro, Nuno F. F. Moreira, Joaquim L. Faria, Olfa Hentati, Adrián M. T. Silva, Mohamed Ksibi

Abstract:

Degradation and mineralization of ibuprofen (IBU) were investigated using Ultraviolet (UV) Light Emitting Diodes (LEDs) in TiO2 photocatalysis. Samples of ultrapure water (UP) and a secondary treated effluent of a municipal wastewater treatment plant (WWTP), both spiked with IBU, as well as a highly concentrated IBU (230 mgL-1) pharmaceutical industry wastewater (PIWW), were tested in the TiO2/UV-LED system. Three operating parameters, namely, pH, catalyst load and number of LEDs were optimized. The process efficiency was evaluated in terms of IBU removal using high performance liquid chromatography (HPLC) and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Additionally, the mineralization was investigated by determining the dissolved organic carbon (DOC) content. The chemical structures of transformation products were proposed based on the data obtained using liquid chromatography with a high resolution mass spectrometer ion trap/time-of-flight (LC-MS-IT-TOF). A possible pathway of IBU degradation was accordingly proposed. Bioassays were performed using the marine bacterium Vibrio fischeri to evaluate the potential acute toxicity of original and treated wastewaters. TiO2 heterogeneous photocatalysis was efficient to remove IBU from UP and from PIWW, and less efficient in treating the wastewater from the municipal WWTP. The acute toxicity decreased by ca. 40% after treatment, regardless of the studied matrix.

Keywords: acute toxicity, Ibuprofen, UV-LEDs, wastewaters

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711 Evaluation of Gene Expression after in Vitro Differentiation of Human Bone Marrow-Derived Stem Cells to Insulin-Producing Cells

Authors: Mahmoud M. Zakaria, Omnia F. Elmoursi, Mahmoud M. Gabr, Camelia A. AbdelMalak, Mohamed A. Ghoneim

Abstract:

Many protocols were publicized for differentiation of human mesenchymal stem cells (MSCS) into insulin-producing cells (IPCs) in order to excrete insulin hormone ingoing to treat diabetes disease. Our aim is to evaluate relative gene expression for each independent protocol. Human bone marrow cells were derived from three volunteers that suffer diabetes disease. After expansion of mesenchymal stem cells, differentiation of these cells was done by three different protocols (the one-step protocol was used conophylline protein, the two steps protocol was depending on trichostatin-A, and the three-step protocol was started by beta-mercaptoethanol). Evaluation of gene expression was carried out by real-time PCR: Pancreatic endocrine genes, transcription factors, glucose transporter, precursor markers, pancreatic enzymes, proteolytic cleavage, extracellular matrix and cell surface protein. Quantitation of insulin secretion was detected by immunofluorescence technique in 24-well plate. Most of the genes studied were up-regulated in the in vitro differentiated cells, and also insulin production was observed in the three independent protocols. There were some slight increases in expression of endocrine mRNA of two-step protocol and its insulin production. So, the two-step protocol was showed a more efficient in expressing of pancreatic endocrine genes and its insulin production than the other two protocols.

Keywords: mesenchymal stem cells, insulin producing cells, conophylline protein, trichostatin-A, beta-mercaptoethanol, gene expression, immunofluorescence technique

Procedia PDF Downloads 189
710 Experimental and Numerical Performance Analysis for Steam Jet Ejectors

Authors: Abdellah Hanafi, G. M. Mostafa, Mohamed Mortada, Ahmed Hamed

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The steam ejectors are the heart of most of the desalination systems that employ vacuum. The systems that employ low grade thermal energy sources like solar energy and geothermal energy use the ejector to drive the system instead of high grade electric energy. The jet-ejector is used to create vacuum employing the flow of steam or air and using the severe pressure drop at the outlet of the main nozzle. The present work involves developing a one dimensional mathematical model for designing jet-ejectors and transform it into computer code using Engineering Equation solver (EES) software. The model receives the required operating conditions at the inlets and outlet of the ejector as inputs and produces the corresponding dimensions required to reach these conditions. The one-dimensional model has been validated using an existed model working on Abu-Qir power station. A prototype has been designed according to the one-dimensional model and attached to a special test bench to be tested before using it in the solar desalination pilot plant. The tested ejector will be responsible for the startup evacuation of the system and adjusting the vacuum of the evaporating effects. The tested prototype has shown a good agreement with the results of the code. In addition a numerical analysis has been applied on one of the designed geometry to give an image of the pressure and velocity distribution inside the ejector from a side, and from other side, to show the difference in results between the two-dimensional ideal gas model and real prototype. The commercial edition of ANSYS Fluent v.14 software is used to solve the two-dimensional axisymmetric case.

Keywords: solar energy, jet ejector, vacuum, evaporating effects

Procedia PDF Downloads 590
709 Means of Securing Graves in the Egyptian Kingdom Era

Authors: Mohamed Saeed Ahmed Salman

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This research aims to study the means of securing graves in the Egyptian kingdom era, and revolves around many basic ideas used by the ancient Egyptian to protect his graves from thieves, which included architectural characteristics, which gave it importance only others. The most important of which was the choice of the place of the grave, which chose a kohl place in the desert to protect the graves, which is the valley of kings, and whether the choice of that place had an impact in protecting the grave or not, in addition to other elements followed in the architectural planning, which was in the valley of kings. The multiplicity of the tomb, the construction of the well chamber to deceive the thieves by the end of the graves suddenly, the construction of the wells of the tombs, which contained the burial chamber at the bottom of the main well and the effect of all these factors on the graves, and this shows the importance of the graves to the ancient Egyptian and his belief in resurrection and immortality. The Egyptian resorted to the elements of protection and was a religious worker by The protector gods and special texts to protect the deceased from any danger to protect the tomb. As for the human factor of securing the tomb through human guards (police) and security teams based on the guard and the words indicating the protection and the guard teams and the teams of the majai. The most important developments that arose on the cemetery from Tamit entrance, corridors, chambers, burial chamber and coffin, and the use of sand to close the well after from one cemetery to another and from time to time where it was built in the late period inside the temple campus to be under the attention of the priests and their protection, as the study dealt with an analytical study For the means of securing graves in the Egyptian kingdom period.

Keywords: Egyptian kingdom, ancient Egyptian, securing graves, Means of securing graves, Egypt, archaeology

Procedia PDF Downloads 45
708 Morpho-Syntactic Pattern in Maithili Urdu

Authors: Mohammad Jahangeer Warsi

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This is, perhaps, the first linguistic study of Maithili Urdu, a dialect of Urdu language of Indo-Aryan family, spoken by around four million speakers in Darbhanga, Samastipur, Begusarai, Madhubani, and Muzafarpur districts of Bihar. It has the subject–verb–object (SOV) word order and it lacks script and literature. Needless to say, this work is an attempt to document this dialect so that it should contribute to the field of descriptive linguistics. Besides, it is also spoken by majority of Maithili diaspora community. Maithili Urdu does not have its own script or literature, yet it has maintained an oral history of over many centuries. It has contributed to enriching the Maithili, Hindi and Urdu languages and literature very profoundly. Dialects are the contact languages of particular regions, and they have a deep impact on their cultural heritage. Slowly with time, these dialects begin to take shape of languages. The convergence of a dialect into a language is a symbol and pride of the people who speak it. Although, confined to the five districts of northern Bihar, yet highly popular among the natives, it is the primary mode of communication of the local Muslims. The paper will focus on the structure of expressions about Maithili Urdu that include the structure of words, phrases, clauses, and sentences. There are clear differences in linguistic features of Maithili Urdu vis-à-vis Urdu, Maithili and Hindi. Though being a dialect of Urdu, interestingly, there is only one second person pronoun tu and lack of agentive marker –ne. Although being spoken in the vicinity of Hindi, Urdu and Maithili, it undoubtedly has its own linguistic features, of them, verb conjugation is remarkably unique. Because of the oral tradition of this link language, intonation has become significantly prominent. This paper will discuss the morpho-syntactic pattern of Maithili Urdu and will go through a sample text to authenticate the findings.

Keywords: cultural heritage, morpho-syntactic pattern, Maithili Urdu, verb conjugation

Procedia PDF Downloads 180
707 Adhesion of Staphylococcus epidermidis and Staphylococcus aureus to Intravascular cannulae

Authors: Ghadah Abusalim, Suliman Alharbi, Hesham Khalil, Milton Wainwright, Mohammad A. Khiyami

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The use of implantable foreign devices in medicine has recently increased dramatically. Intravascular cannulae and catheters are used to administer fluids, medications, parenteral nutrition, and blood products in order to monitor hemodynamic status and also to provide hemodialysis. The early and late failure of inserted or implanted devices is largely the result of bacterial infection and may lead to the disruption of integration between the device and the tissues which surround it. Staphylococcus aureus and Staphylococcus epidermidis are widely considered to be the most common organisms causing device-related infection. Our study showed that S. aureus and S. epidermidis adhered to intravascular cannulae made up of PTFE, SPTFE and vialon. Adhesion of S. epidermidis and S. aureus to intravascular cannulae varied significantly depending upon the type of material used and the presence of coating materials. Both bacteria adhered less to PTFE followed by Vialon and SPTFE and the adhesion capacity of S. aureus and S. epidermidis increased over time. Coating intravascular cannulae with human serum albumin inhibited the adhesion of S. aureus and S. epidermidis to these cannulae, and pretreatment of cannulae with fibronectin inhibited the adhesion of S. epidermidis but increased the adhesion of S. aureus to all types of cannulae. Pretreatment of cannulae surface with potassium chloride or calcium chloride increased the adhesion of S. aureus and S. epidermidis to cannulae, suggesting a role for electrostatic forces in the mechanism of such adhesion. This study will hopefully clarify the mechanism of adhesion and provide possible means of preventing such adhesion either by the use of better material coatings or by interfering with the process of adhesion by targeting bacterial structures responsible for it. Currently we recommend the use of PTFE cannulae as they exhibit a lower bacterial adhesion capacity compared to the other tested cannulae.

Keywords: Staphylococcus epidermidis, Staphylococcus aureus, adhesion, cannulae, PTFE, Vialon

Procedia PDF Downloads 317